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91.
Fei Huo Xiaohui Wang Yaoyao Zhang Xu Zhang Jianxiong Xu Wangqing Zhang 《Macromolecular chemistry and physics.》2013,214(8):902-911
The RAFT polymerization of styrene in a solvent consisting of a water/alcohol mixture with different water contents is performed and the solvent effects on polymerization kinetics, polymer chain propagation, and polymer particle growth are evaluated. It is found that the solvent affects the RAFT polymerization kinetics greatly, and the apparent polymerization rate constant (Kp app) increases with an increase in the water content of the water/alcohol mixture. In addition, RAFT polymerization in a water/alcohol mixture with a higher water content affords better control of the polydispersity index (PDI) of the synthesized polymers. Furthermore, the solvent also exerts a great influence on the growth of the polymer particles. Hollow particles are formed either at the initial polymerization with low monomer conversion or in the solvent with a low water content, whereas solid polymer particles are produced either at high monomer conversion or in the solvent with a high water content.
92.
《The Knee》2022
BackgroundIn recent years, transcatheter arterial embolization (TAE) using imipenem/cilastatin (IPM/CS) has attracted attention as a treatment for relieving osteoarthritis (OA) pain. However, IPM/CS is not approved by Japanese medical insurance for use as an embolic material. Therefore, it is necessary to develop new embolic materials for TAE to relieve OA pain. The purpose of this study was to develop a swine model of knee arthritis and embolize abnormal neovessels (ANs) using two different embolic materials. We compared the embolic effects and tissue damage in knees.MethodsKnee arthritis was induced by intra-articular injection of papain into 12 knees in six female swine. The swine were divided into two groups of three swine each (six knees per group) for embolization of ANs in the knees with either IPM/CS or soluble gelatin sponge particles (SGSs). Three days after embolization, we compared the embolic effects using angiography and the tissue damage histopathologically.ResultsANs were observed in all 12 knees at 42 days after papain injection. The ANs disappeared and the patent arteries were recanalized 3 days after TAE in all 12 knees. Histopathological evaluation revealed synovitis changes, such as synovial thickening and inflammatory cell infiltration, in all 12 knees. There was no evidence of skin or muscle necrosis in either group. The appearance of ANs, recanalization of the parent arteries, and histopathological outcomes were not significantly different between the two groups.ConclusionSGSs were as safe as IPM/CS for TAE of ANs in this swine model of knee arthritis. 相似文献
93.
针对人工滴染血涂片出现的染色不均匀、效率较低等问题,提出一种基于压力旋流雾化喷头对血涂片进行喷染的方法。采用数值模拟与实验相结合的方法对瑞氏-姬姆萨染液雾化过程进行分析,并探索最佳喷染参数。首先利用ANSYS软件仿真计算染液在喷头内部的流动状态,然后使用相机和喷雾激光粒度仪搭建喷头外部雾化场实验平台,喷头外部入口压力分别选取0.10、0.12、0.14、0.16、0.18、0.20、0.22、0.24 MPa,测量染液的雾化角以及喷头正下方10~50 mm的雾化区域内测量点的雾滴粒径参数(Dv10,Dv90和雾滴体积中径Dv50),计算粒度分布跨度S,并在此基础上开展血涂片喷染研究,并对比了人工滴染和喷染后的细胞图像背景灰度参数。仿真结果表明:染液在压力旋流雾化喷头出口处形成高速液膜,为形成雾化场提供理论依据。实验结果表明:当喷头入口压力为0.20 MPa时,距离喷头正下方35 mm处喷染界面具备最优的雾化质量,此时喷头雾化角为76.13°,雾滴体积中径为75 μm,雾滴粒度分布跨度为1.72。基于该参数条件进行喷染后的细胞图像背景灰度参数与滴染相比存在显著性差异(P<0.01),喷染后的细胞图像背景灰度显著降低。研究结果表明,压力旋流雾化喷头可以应用于血涂片染色,并且喷染后的血涂片染色均匀,具备良好的染色效果,为血涂片染色提供了新的方案。 相似文献
94.
Ismail Cem Yilmaz Emre Mert Ipekoglu Artun Bulbul Nilsu Turay Muzaffer Yildirim Irem Evcili Naz Surucu Yilmaz Nese Guvencli Yagmur Aydin Bilgi Gungor Berfu Saraydar Asli Gulce Bartan Bilgehan Ibibik Tugce Bildik layda Baydemir Hatice Asena Sanli Basak Kayaoglu Yasemin Ceylan Tugce Yildirim Irem Abras Ihsan Cihan Ayanoglu Sefa Burak Cam Eda Ciftci Dede Merve Gizer Osman Erganis Fahriye Sarac Serdar Uzar Hakan Enul Cumhur Adiay Gamze Aykut Hivda Polat Ismail Selim Yildirim Saban Tekin Gulay Korukluoglu Hasan Ersin Zeytin Petek Korkusuz Ihsan Gursel Mayda Gursel 《Allergy》2022,77(1):258-270
95.
Virginie F. Tisse Floran Prades Remi Briquel Christophe Boisson Timothy F. L. McKenna 《Macromolecular chemistry and physics.》2010,211(1):91-102
The role of certain morphological properties of different silica used as supports for metallocene catalysts was investigated in order to quantify their eventual influence on the kinetics of ethylene polymerisation in heptane slurry, as well as on the polymer properties. It was shown that there is no clear link between porosity and observed activity with some highly porous silica producing relatively inactive supported catalysts. It was further shown that within a batch of silica, the particle size had a significant impact on observed kinetics. While it appears that there is possibly some diffusion resistance encountered in the larger particles, it was also shown that prolonged contact between the support and the alkylating agent could increase reaction rates in the larger particles.
96.
目的 研究重组人乳头瘤病毒 6型 (humanpapillomavirustype 6 ,HPV 6 )病毒样颗粒(virus likeparticle ,VLP)的免疫原性。方法 重组杆状病毒在昆虫细胞中表达制备的HPV 6L1VLP(L1 VLP)和HPV 6L1+L2VLP(L1+2 VLP)经鉴定后 ,用于免疫BALB/c小鼠 ,对诱导的体液免疫和细胞免疫反应进行了检测。结果 电镜观察显示L1 VLP和L1+2 VLP二者形态上无明显差异 ,为圆形颗粒 ,直径约 5 0nm ,SDS PAGE和Westernblot分析表明 ,L1+2 VLP中L1和L2蛋白摩尔比例为 4∶1。用ELISA法测定免疫小鼠血清抗体滴度 ,加佐剂L1 VLP免疫组和加佐剂L1+2 VLP免疫组血清针对HPV 6L1VLP的滴度在 1∶10 0 0 0以上 ,高于未加佐剂组免疫血清滴度 (1∶2 0 0 0 ) ,L1+2 VLP免疫诱导出了特异于L2抗原的抗体。血清抗体主要识别HPV 6构象依赖性抗原表位 ,与HPV 11抗原显示出一定的交叉反应 ,而与HPV 16无明显交叉反应。免疫小鼠脾淋巴细胞体外经HPV 6L1VLP再激活后出现了特异性增殖反应 ,3H TdR掺入值与未免疫组之间差异有显著性 (P <0 .0 1) ,L1 VLP和L1+2 VLP两组间差异无显著性 (P >0 .0 5 ) ,L1 VLP和L1+2 VLP免疫组刺激指数 (SI)分别为 6 .4和 6 .2 ,阴性对照组SI为 1.1。HPV 6L1VLP再刺激特异地诱导免疫组脾淋巴细胞IL 2和IL 10分 相似文献
97.
目的 构建半水硫酸钙和纳米羟基磷灰石为主的复合人工骨材料并对其注射性能、凝固性能和机械强度的影响因素进行考察.方法 测试不同液固比条件下复合材料的注射特性,25℃和37℃时分别测试不同液固比、不同二水硫酸钙促凝剂条件下的材料初、终凝时间和压缩强度,均与纯硫酸钙作对比.结果 液固比0.50以上时注射性能满意.无论何种液/固比,复合材料的凝固时间均较硫酸钙延长,37℃下的凝固时间较25℃下延长.一定范围内促凝剂用量过大或过小均使凝固时间延长.液固比越大或促凝剂用量越高,材料压缩强度越低.纳米磷灰石含量增大则材料强度降低.结论 合理掌握纳米磷灰石的比例,液固比和促凝剂的用量,是开发可注射纳米人工骨的关键. 相似文献
98.
A method for quantitating the number of polymorphonuclear leukocytes (PMNs) adhering to endothelial cells in vitro is presented. Confluent human umbilical vein endothelial cells cultured in 24-well multiplates and treated with tumor necrosis factor (TNF ) were incubated subsequently wioth PMNs which adhere to the endothelial cell as a function of TNF concentration. Adherent PMNs and endothelial cells were proteolytically dissociated from the multiwell and, using an electronic particle counter, the number of endothelial cells and PMNs were determined simultaneously on the basis of size. The average number of PMNs adhering per endothelial cell was then calculated. The method is rapid and precise and offers an alternative to both tedious microscopic counting and the hazardous radiolabeling of PMNs. 相似文献
99.
100.
目的 回顾性分析颅底高血运脑膜瘤患者外科手术前瘤体供血动脉栓塞术,评估其有效性及安全性.方法 收集2008年至2015年6月接受全脑DSA检查并证实血运丰富的73例颅底脑膜瘤患者临床资料,就外科手术前瘤体供血动脉栓塞及栓塞相关并发症,瘤体切除术中出血量、手术时间进行分析.结果 外科手术前31例患者(栓塞组)中接受Glubran胶栓塞16例,聚乙烯醇(PVA)颗粒栓塞14例,Glubran胶联合PVA颗粒栓塞1例;42例患者未接受栓塞(未栓塞组).外科手术中平均出血量在栓塞组为693 ml,未栓塞组为903 ml,差异有统计学意义(P=0.047);瘤体完全切除率在栓塞组为87.1%,未栓塞组为66.7(P=0.134).栓塞组无栓塞相关并发症发生.结论 颅底高血运脑膜瘤外科手术前栓塞可有效地降低术中出血量,是安全有效的辅助治疗方法. 相似文献